Navigational plotting device



May 9, 1950 R. DUUS 2,506,584

NAVIGATIONAL PLO'ITINGv DEVICE Filed May 22, 1946 2 Sheets-Sheet 1 F/ .i F1 2 11V VEN TOR ATTOR/t/E) May 1950 R. DUUS 2,506,584

NAVIGATIONAL PLOTTING DEVICE Filed May 22, 1946 2 Sheets-Sheet 2 Fig.5

IN V EN TOR. RA Y 0 00s ATTOR/VE 1 Patented May 9, 1950 UNITED STA'TESI QFFIC E 2,506,584 NAVIGATIONAL PLOTTING' DEVICE Ray Duns, United States Navy, Beverly Hills, Calif..-

Application May 22, 1946,'Serial N 0. 671,485

(Granted. under the act of (March 3, 1883, as amended AprilSO; 1928; .370 O. G. 757) 3 Claims.

sociated .devices,..it. is desirable to have a. means for showing, not only ,the present location of objects surrounding aship, but. to also have-means whereby the location of-such surrounding objects in the. period immediatelypreceding any present moment may .beltraced. While thisinvention is quite suitable vfor use inconjunction with radar equipment it is not. necessarily so limited, it. being understood that. information plottedmay be received .from .any. source reporting the position of.-

objects surroundingaship.

Accordingly,.it. is an-object of; this invention to provide meanswhereby positionsof objects .sur-

rounding a. predetermined 1 point. may be plotted.-

It. is another. object to provide means whereby temporal changes in the position of objects-surrounding a predeterminedpoint may be plotted quickly and easily.

It is another object toprovide. apparatuseffective to produce, on a substantially plane surface, aspot of. lightcorresponding to an. object spacedffrom a predetermined point, which. spot of light may be moved .quickly andeasily to other.

positions corresponding to other objects...

In accomplishing these andother objects of the present invention, I have provided improvedd tails of structure, the preferred forrnsoi which. are illustrated in the accompanying drawings.

wherein Fig.1 shows. an elevation of 'apparatus-em=- bodying, this invention;

Fig; 2 is a detailed view of one embodiment of. a particular. portion of the apparatus shown .com-..

pletely in Fig. 1;

Fi'gs.,-3 and 4 illustrate"alternativeapparatus for accomplishing thesame function performed.

by the structure shown in Fig, 2;

Fig; 5 is ajfurther embodiment of apparatus which may be alternatively. incorporated ,in the.

structure shown generally in Fig. 1; and

Fig. 6 illustrates an: additional, alternative structure which maybe utilized in the apparatus;

shown generally in Fig. 1.

The apparatus of this invention consistsgem. erally of a plotting table havingatranslucent. top, beneath whichand spaced appreciably there-v from, is means for ,generatinga beam of light.

The light. generating .meansis so arranged that A by tilting and rotating, the beam of light may. be

directed to any point on. .the undersurface of the translucent table top. In this way, objects. surrounding ones own ship, represented-bye. .point on the table top directly over the light generatingmeans, may be-momentarily indicated and .plotted, for example, withcrayon. or, other. meansfor making an easily removable mark.-

Referring. more ,specificallyto the drawings. the general. form. of .the apparatus embodying. this invention isshown in Fig. 1, wherein H1 represents a plotting tablemounte'd on a deck. of a ship. Table It! has acircular top 12, preferably of translucent. material and circular-in. form. A base. 13 spaced from. table top J2 has.

rotatably mounted thereon a carrier 14. Motive means in the form of motor |5,.mounted on.basel 3, is provided for rotating carrier I4 with respect tobase I3 about an aXis normalto tabletop l2. The operative connection between motor l5 and carrier J4 is shown schematically at. IB..

Pivotally mounted on carrier 14 about an axis I1 is alight tube Hi.v Means,.such.as .a reversible motor, [9, are mounted on carrier-l4 for. rotating light I8 about axis l'l.

A second light tube 20 may be provided, directed. upward along the rotational. axis of carrier .14. If desired, base I 3 may be movably mounted .on

cross members 2!. In certain cases. it maybe desirable to employ as base l3the movable'carriage of aconventional "deadreckoning tracer.

As is well known in the art, a dead reckoning. tracer comprises a carriage movablealong ,two..

perpendicular axes in accordancewith navigae.

tional information feel to the dead reckoning.

tracer Tracing means such as a light beam are provided On thecarriage, so that the calculated a position oftheship, controlled by themotion transmitted to the carriage, may be continuously indicated ona map-marked surface.

The application of the present inventionto such a dead reckoning tracer, will be readily evi-, dentaby .understandingthat base l3 of the pres entlinvention may consist of the above mentioned carriagecof thedead reckoning tracerhmovableo in a plane. parallel to deck I I. along mountingmembers 2 I...

It is not-necessary in the practice of-this invention to movably mount base 13; if desired, it

may be fixedly .mounted with respect .to. table top,.l2..v

In the-embodiment shownin Fig. 1, motors. l5, and tears preferably teleemotors, or .other deviceseffe'ctive toassumela predetermined angu.-. larpositicn- .in iaccordancevwith electrical con-.-

trol signals fed thereto. Such devices are marketed under the names Selsyn, Synchro, Teletorque, and similar names. It will be understood that energy for motor I9, mounted on rotatable carrier I4, is fed thereto through suitable slip ring arrangements, not shown, as is energy for the lamps necessarily required inside light tubes I8 and 20.

Light tubes I8 and 20 may, if desired, be replaced by any means for producing a narrow angle, directable beam of light.

Fig. 2 shows an alternative means for transmitting tilting position to light tube I8, represented in Fig. 2 by the reference numeral ISa. Carrier floor I ia of Fig. 2, corresponding to carrier I4 in Fig. 1, is rotatable about the axis of tube 20a, being supported and rotated by any suitable means not shown. It will be understood that such means are similar to the means shown generally in Fig. 1 for the correspondingly referenced elements. Positioning motor I9a, effective to determine the tilting angle of light tube I8a, is mounted on base 53a, instead of being mounted on carrier Me, as with the corresponding motor it in Fig. 1.

Motor IEia rotates a pinion 2i, meshing with a rack 22 slidably mounted in base I3a. At the top of rack 22 is attached a swivel member in the form of ring 23 pivoted about a vertical axis as shown. Attached to, and extending upward from, ring 23 is a wire 24 passing through opening 25 in carrier Ma, and attached at its upper end 25 to one side of a cam 21. Cam .2! is pivoted on carrier I 4a at 28 and biased clockwise by any suitable means as shown by arrow 29.

The surface of cam 21 cooperates with a toe 3i attached to light tube Ilia, which is pivoted about axis Ila. Suitable means are provided for biasing light tube I8a clockwise as represented by the arrow 3 I.

The operation of the light tilting apparatus shown in Fig. 2 will be readily evident by visualizing that as motor Illa rotates pinion ZI, rack 22 is pulled down. This causes counterclockwise rotation of cam 21 about axis 28, allowing toe 34 to move inwardly about axis IIa by the action of biasing means 3 I, thus tilting light tube Isa to the desired angle. At the same time, carrier I ia may be freely rotated about its axis (coinciding with wire 24) through the swiveling action of ring 23 in the top of rack 22. It is thus seen that two completely independent motions may be imparted to light tube IBa. Rotation of the tube is effected by rotation of carrier I400, while tilting of the tube is effected by reciprocation of rack 22.

An alternative meansfor transmitting the reciprocation of rack 22 into rotation of light tube I8a is illustrated in Fig. 3. Ring 23a, corresponding to ring 23 inFig. 2, has attached to it a wire 24a, the upper end of which is attached at 26a to the surface .of a disk sector Z'Ia rotatable about axis 28a on carrier I411. The lower portion of wire 24a, i. e., the portion between ring 23a and carrier I4b must coincide with the rotational mounting axis of carrier I41). If it is desired to offset the effective line of operation of wire 240., a suitable idler pulley 32, pivotally mounted at 33 to carrier [42), may be provided. Light tube I82) is fixedly mounted with respect to sector 21a, and like the latter is rotatable about axis 28a.

An alternative means for vertically reciprocat- 4 Gear 2Ib is internally threaded and coacts with the external threads of a lead screw 2211 having swivel pin 23b pivotally mounted at the top thereof.

The operation of the modified apparatus shown in Fig. 4 will be readily evident by referring to the correspondingly numbered elements of Fig. 2. Rotation of pinion Zia causes gear Zlb to rotate, thereby reciprocating lead screw 22a through the action of the threads thereon. It will be understood that lead screw 22a is restrained from rotating, as by means of keying in base I312.

A somewhat different form of light beam generator than described before is illustrated in Fig. 5, wherein I40, corresponding to carrier member I4 in Fig. 1, is rotatably mounted about a vertical axis and is rotated by some means similar to motor I5 of Fig. 1. The actual light carrying apparatus is mounted on a separate carrier member Hid, which includes a horizontal, transverse, magnetized member 35. Carrier I includes electro-magnets 35 and 31, energized through wires 33 and 39. Carrier I id is, like I 40, rotatably mounted on base I3 about the same vertical mounting axis as carrier I40. Carrier Md is freely rotatable, being rotated by magnetic attraction on the base l3 into a position such that magnet 35 is aligned with electro-magnets 3S and 3'! whenever the latter are energized.

ing of wire 24 in Fig. 2 is shown in Fig. 4..

Pivotally mounted at I'Ib on carrier I411 is a light tube I80, having at the bottom thereof an electric light 40. It will be understood that a light similar to light 40 is included in the aforementioned light tube I8, the showing thereof being omitted in this former instance in the interest of simplicity. Light tube I includes at its lower extremity a toe 4I fixedly attached thereto, at the end of which is pivoted at 43 a solenoid plunger 42. Plunger 42 reciprocates within a solenoid 44, attached at one side of carrier Md. Suitable means biasing light tube I8c counter-clockwise about axis I'Ib are represented by arrow 45.

The manner in which light tube I80 may be I directed toward any given point on table top I2 will now be reviewed. The radial displacement of the light spot appearing on top I2 is determined by the magnitude of the force exerted by solenoid 44 on plunger 42, acting against biasing means 45. This force in turn depends on the magnitude of the current in solenoid 44. The angular position of the light spot about the vertical axis of carrier Md, at the radius determined by the magnitude of the energizing current in solenoid 44, is determined by the position of electro-magnets 36 and 31, mounted on carrier I40. In practice, carrier I40 is rotated on base I3 to a desired angular position, or azimuth, by suitable means such as motor l5. Upon energization of magnets 36 and 31, magnetic armature 35 assumes a position in line with magnets 36 and 31, thereby disposing carrier I 4d at the desired azimuth.

Light tube I80 is telescoped as shown at 46, and focusing means in the form of arm 41 are provided; rotation of light tube I 80 about axis I'Ib causes arm 4! to shorten the focus oflens 48, thereby focusing. the light spot at a greater distance. This provision is made to compensate for the fact that as light tube IBc is tilted outward the beam must focus on top I2 at an increasing distance.

The energizing circuit for the apparatus of Fig. 5 is shown comprising a source of voltage 49, one side of which is connected to a double pole,

double throw switch 59, normally biased upwardly. Energy for solenoid 44 traverses connection switch 50, variable resistor 52, slip ring 53 and returns through slip ring 54 and connections '55 to the other side of energy source 49. Energy for electro-magnets 36 and 37 is provided through connection 38, electro-magnet 36, electro-magnet 3T, connection 39, switch 59 (when pressed closed) and connection 5|.

Energy for light 43 is provided through connection 5!, switch 50, slip ring 56 and returns through slip ring 51 to connection 55.

Arm 58 of variable resistor 52 is connected to a range determining means, so that the position of arm 58 is a uni-valued function of the range, or distance from the center point, at which it is desired to have the light spot appear. Thus, with switch 50 in the position shown, solenoid 44 is energized with a current proportional to the desired range thereby tilting light tube 18 a proportionate amount.

When it is desired to move the spot of light on top [2 to designate another plotting point, carrier 140 is first rotated by motor l5 to the desired azimuth. Switch 50 is then depressed, energizing electro-magnets 36 and 31 which rotate [4d to the desired angular position. Upon release of switch 50, carrier 14d remains as placed, and light 40 is energized simultaneously with solenoid 44 to cause the light spot to appear at the proper range. With each appearance of the light spot, a dot may be marked on table top l2 to plot the indicated position of the object.

This form of the invention does not carry a vertical tube like the tube 29, and hence is best suited for plotting from a stationary point such as a ground radar station.

In Fig. 6 is illustrated a still further alternative light generator for use with polar plotting table [9. Numeral He represents a rotatable carrier of the general form shown at I4 and illustrated more specifically at 140 in Fig. 5. Like I40, carrier Me includes a pair of electro-magnets 36a and 31a diametrically disposed around the vertical axis.

Arranged on the axis between electro-magnets 36a and 31a is a container 59 fixedly mounted on base l3 and having at the top thereof a socket Bil into which may be fitted a ball 6 I. On the top of ball 6|, which is preferably cut to a hemisphere, is mounted a mirror 62 upon which a beam of light may be directed from a source of light 93 directly overhead. Depending from ball 61 in socket 60 is a polarized magnetic member 64 constituting also a counterweight tending to return mirror 62 to a horizontal position. If desired, damping fluid 65 may be placed in container 59 to stabilize universal motion of member 64. Electro-magnet 31a is energized with a constant current. Electro-magnet 36a is energized, through variable resistor 52a corresponding to 52 in Fig. 5, with a current proportional to the range of the object to be plotted.

The operation of the modification shown in Fig. 6 is as follows:

Carrier Me is angularly positioned in accordance with the azimuth of the object to be plotted. Arm 58a is positioned in accordance with the range of the object to be plotted. Upon energization of electro-Inagnet 36a through resistor 52a, magnet 64 will be drawn toward (or away from, depending upon the polarization of 36a and 94) magnet 3611, thereby determining the angular position of the light spot. The extent to which magnet 54 is pulled from its vertical position against the action of gravity is determined by the magnitude of the current in electro-magnet 36a. Thus carrier Me determines not only the azimuth of the light spot, by its angular position; but also determines the range of the light spot, by the magnitude of the current in electro-magnet 360..

Like the modification of Fig. 5, this form does not carry an upright tube 20, and hence is best suited for ground station use.

Operation The general operation of the apparatus of Fig. 1 will now be briefly described, it being understood that each of the modifications described after Fig. 1 utilizes slightly different operation steps, as already described. Dead reckoned information is fed to base l3 continuously, ther by causing the light beam from light tube 29 to form a spot continuously reporting the instantaneous position of own ship. Range and azimuth information regarding an external object such as another ship is transmitted to motors I9 and i5, respectively, causing the light beam to be directed upon top l2 at a point corresponding to the position of the other ship. This position having been marked on top l2, new range and bearing information is transmitted to motors l9 and I5 and another point plotted.

All objects of interest having been plotted, the above procedure is continually repeated, thereby indicating temporal changes in positions of surrounding objects. In this way a continuous check on the position and movement, either relative or absolute, of surrounding objects, may be maintained at all times.

While I have shown embodiments of my invention, it is susceptible to modification without departing from the spirit of the invention. I do not wish, therefore, to be limited by the disclosures set forth, but only by the scope of the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim:

1. Polar plotting apparatus comprising a substantiall plane surface, a base spaced from said plane surface, a first carrier rotatably mounted on said base about an axis normal to said plane surface, a light tube pivoted on said first carrier about an axis transverse of said tube and parallel to said plane surface, a first generator of magnetic flux mounted on said first carrier, a second carrier rotatably mounted on said base coaxially with said first carrier and having a second generator of magnetic flux coacting magnectically with said first generator, means to selectively energize one of said generators, means to rotatably position said second carrier, a, solenoid mounted on said first carrier having a plunger, means connecting said plunger and said tube to translate plunger movement to tube rotation, and variable voltage means effective to energize said solenoid.

2. Polar plotting apparatus comprising a base, a carrier rotatably mounted on said base, magnetic flux producing means on said carrier effective to produce a flux perpendicular to the rotative axis of said carrier, a magnetic sensitive member rotatably mounted on said base for rotation about said axis and rotatable into position corresponding to the angular position of said carrier, variable focus light beam means pivoted on said member about an axis perpendicular. to said carrier axis, means for controlling the angular position of said light beam means on said member, and a focusing arm connected between said member and said light beam means efiective to change the focus of said light beam means in accordance with the angular position thereof.

3. Polar plotting apparatus comprising a base, a carrier rotatably mounted on said base, magnetic flux producing means on said carrier effective to produce a fiux perpendicular to the rotative axis of said carrier, a magnetic sensitive member rotatably mounted on said base for rotation about said axis and rotatable into position corresponding to the angular position of said carrier, light beam means pivoted on said member about an axis perpendicular to said carrier axis, means for controlling the angular position of said light beam means on said member, circuit means for energizing said flux producing means, circuit means for energizing said controlling means, circuit means for energizing said 8. light beam means, and two-positionswitch means connected in said circuit means effective in one position to energize said controlling means and said light beam means, and effective in the other position to energize said flux producing means.

RAY DUUS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

